This invention relates to alarm devices and, more particularly, alarms coupled to a belt to issue an alarm upon a change in the dimension of the waist of the wearer.
Alarm devices have been previously proposed. These alarm devices, however, have been used to improve the posture of the wearer. Thus, for example, Verhaeghe, in U.S. Pat. No. 3,582,935, provides for a housing secured to the belt of a wearer. The housing is hollow and has an aperture on the housing wall adjacent to the waist of the wearer. Within the housing are an alarm buzzer and a battery. An electrical switch is secured to the housing and provided with a contact arm which is secured to the housing and extends into the aperture and abuts the waist of the wearer. Any expansion of the abdomen, as caused, for example, by a change in the posture of the wearer, causes the contact arm to be moved outwardly with reference to the wearer, thereby closing the switch and energizing the alarm. The disadvantage of this device is that if the enlargement of the waist is not as a result of a change in posture, or if the expansion is not directly outwardly at the location of the contact arm, the alarm will not sound. Ordinarily, as a waist expands, the pulling on a belt would be circumferential with respect to the waist. In such an instance, the device proposed by Verhaeghe will be unlikely to issue an alarm.
Palmer, in U.S. Pat. No. 3,670,320, proposes a similar device to that proposed by Verhaeghe. Palmer's device provides a housing to which both ends of a belt are attached. The free ends of the belt, however, are attached to a buckle which is secured at the back of the user--a decided disadvantage. In the alarm housing is an L-shaped arm, to one leg of which is attached one part of the belt. Another leg of the arm is secured asymmetrically within the housing and is held in position slidably between studs and a support wall within the housing. The end of the leg within the housing is connected to the housing by a coiled spring. Attached to the leg is a contact arm. As the belt moves outwardly, due to the expansion of the waist of the user, the contact engages a switch. Closing the switch completes a circuit which includes an alarm. The device disclosed is bulky, providing a battery holding chamber on the exterior of the belt and the alarm in a chamber between the belt and the wearer.
Both devices have in common certain disadvantages. They do not serve as a belt buckle, but, rather, are housings which are separately securable to a belt. This draws attention to the fact that the wearer is using a separate device for some specialized purpose--a purpose that the wearer may not wish to publicize. Further, each of the above-discussed devices is less concerned with the actual size of a waist than with good posture. For that reason, each measures a uni-directional force. In Verhaeghe, the force must be outwardly with respect to the wearer and at the location of the contact. In Palmer, the force must be circumferential. Non-circumferential forces will cause the arm of the L-shaped member to engage the studs, thereby restricting movement and providing a false reading. Further, each of these devices is in a constant active state.